Archive for the ‘Projects’ Category
In the last couple of weeks we’ve done some new LEGO Robot Challenges and I’m really pleased at how they turned out.
First was my LEGO version of the Hungry Hippo game. The students were tasked with creating a robot that drives around gathering balls and marbles. The robot that collects the most points worth of marbles and balls in 60 seconds wins the challenge. The balls are the colored balls that are included in the robot kits. The large balls are worth 5 points each, the marbles are worth 2 points. Students had to come up with a strategy and then build to that strategy. The best design drove around with a scoop on the front that shoveled the captured balls into a bin on top. Many designs had rotating claws in front to direct the balls into a pen.
About a week into the challenge, students were tasked with doing a design review with another group. They had to critique the other groups’ project and suggest ways to improve the design, then have the same done for their project. All of the groups felt they got something out of the design review process.
The arena was our own Octagon I created out of 1×4’s. Each side of the octagon was 24″ and the sides were held together with masking tape. It was sturdy enough that the robots could bump into the walls and trigger a touch sensor. The plan was to have the robots go head to head in the arena, but they all locked up so badly that each robot did individual one minute runs.
The latest challenge was a rope climb. I first showed the kids a couple short videos on the space elevator and we had a short discussion on the cost benefits of such a system. They were given a short week (4 days) to design a robot that could climb up a rope. I hadn’t tried this before so I didn’t know what to expect. I had a few robots climbing the rope within 30 minutes, so I had to up the ante. Basically, they got a C if the robot climbed the rope. If the climber carried a 0.5 kg weight up the rope, the group got a B. If the robot managed to carry a full kilogram weight up the length of the rope, the students earned the A. Only one group managed the A using an innovative design of tires and belts.
I’m going to challenge them to go back to the drawing board on this one and see who can carry the most weight up the rope. After that, we are going to do Robot Wars in the Octagon. The goal is to disable your opponent or remove them from the ring. It should be fun.
First, let me be completely up front. I borrowed this activity from my pal Deborah Carder. You can find her link in my blogroll, she does great hands-on activities and labs. I met her at NSTA Philly last year, she is the Energizer Bunny of science teachers, I don’t know how she does it.
Anyway, as I had mentioned in earlier posts on momentum, I wanted to do the egg drop competition, but I’m in a one-story building. This year we are doing the “Egg Crash” competition. The basic concept is that teams get 10 sheets of computer paper, 1 meter of masking tape, a pair of scissors, and 20 minutes to construct a free-standing object to safely catch the egg. They drop their own egg from a height starting at 0.5 meters above the top of their structure. The egg is inspected before and after each drop, the higher they go, the more points they win. The surviving eggs are dropped from 0.5 meters higher each round until they all finally break.
I usually allot 25 points for a lab, I will probably go 50 for this one. Deb said she does 100 points, but that’s a test grade and I don’t think a one-day lab should be worth that much. I’m still working out the scoring, but I think I will assign a grade to each height. If they fail at 0.5 m above their structure, they get 30/50, but they also get a single start-over with a new egg. Each 0.5 m interval earns 5 more points. That means surviving 2.0 m earns 50/50. I’m willing to give 5 or 10 extra credit points if they can survive a drop from 2.5 or 3.o meters over the top. I was going to do direct competition for the points, but what if everyone fails at 1.0 meters? With my grading system, they all get 70% since nobody really earned the A or B.
I handed out the Egg Crash Description and Rules on the day we started learning about Momentum. I told them it will be about a week before we do the competition; I wanted them thinking about the problem and their design as we learn about momentum and impulse. This week I will show a great video called “Car Crash Tech.” The video discusses the state of the art auto safety systems and the effects of air bags and other innovations.
I’m hoping for some creative solutions from the kids. Maybe I’ll have a picture or two to post here in a couple of weeks.
Essentially there is a network of these things out there for researchers and educators and the public to use. You just need to know they exist, and now you do. For non-researchers, these robotic telescopes have their interface simplified to make taking pictures relatively painless and error free. These robots sit in a field, all alone, with nobody to talk to, just taking orders for pictures.
There is only a small catalog of 36 objects, not all of which will be visible that evening. Pick one, then the interface asks you for a field of view. For those of you who have never used a telescope, it is essentially a zoom level. For the common folk, you only have one choice, but you do have to select it. Next is the time of exposure. It gives you several options, but it will tell you if it is too long or too short. Last is the filter. Some objects have no filter, others have red, green, and blue. Click on continue, give them an email address, and you will have your pictures delivered some time the next day. I’ve tried it twice now, each time the pictures have arrived after lunch the following day.
If you aren’t aware of how astronomical photos are made, here is a quick lesson. Pictures are taken through different color filters. Through a telescope or the naked eye, everything is just shades of gray. But if you take it through RGB filters, you end up with three different images. Now you color each of those images separately and use special software to merge them into a single image. Ta-da! A full color image you created.
Okay, there is more. Astronomy photos are typically in a format called fits. These images carry tons of information about where, when, settings, etc. You really need a special package to merge these photos, but you are in luck. On the same page is free software and a tutorial to do all this.
Imagine how excited your students will be. You teach them about how light is gathered by a telescope. You talk about how the filters are needed to show the color. The color is real, we just can’t see it, there aren’t enough photons for our eyes. Next up, the students go to the site and select an object to photograph. Their request goes into the queue. Multiple requests of the same object will each have individual pictures. Now you can have them walk through the tutorial and use their own image to combine and create their own astronomical photo. Once done, I would send the lot off to Walmart or CVS or some other inexpensive photo developer and they get to put their own astronomical photo on the fridge. Seriously, I get goosebumps thinking about this lesson.
Like I said, this little secret was worth the cost of NSTA. And I almost stayed home on Saturday.
I wanted to build this robot, but we just didn’t get that far. I’ll save it for my summer program at the community college. After midterm exams, we came back to the robots for a final two weeks of programming.
First up was the touch sensor. I liked this lesson, it added switch blocks (if-then) into the programming. We used it with the “follow the line” activity, but the training software told the kids what to do. This time they had to do it on their own. By now, the CMU software has become only a guideline and a reference for the kids. Their assignment was to teach the robot to move forward until it bumped into something. When that happened, the robot was supposed to stop, say “sorry,” back up a little, turn, and start over. This is actually an easy program, so while they were figuring this out, I build a maze out of textbooks.
Part two of this got tricky. I stopped class and explained how you can find your way out of any maze by simply hugging either the right or left wall. They had to try to get through the maze using the single touch sensor in the front. Only one of my students got this to work, and I actually gave him the method. I won’t give it away. Most of the kids got frustrated because the robot would enter the maze and just bump around aimlessly. I asked them to brainstorm a method of using two or more sensors to get through the maze.
The general solution was to add the ultrasonic sensor. Rather than add the sensor to the front, we added it to either the right or left side. The idea was to have the robot stay a certain distance from the right wall. But if it hit something while following the right wall, it would need to make a left turn and continue. This took a lot of trial-and-error for them. It required two switch blocks, one first for the ultrasonic sensor, then one for the touch sensor, both of them together in a loop.
I made this more interesting by changing and growing the maze each day and requiring that the robot must enter the maze from point A and exit at point B, then do it in reverse. This eliminated the possibility of somebody getting clever and just teaching the path to their robot. I made it a point challenge, 50 out of 50 for the fastest combined time, 45/50 for completing the maze in both directions, 40/50 for completing it in one direction, and 35/50 for trying until they ran out of time. Slackers got less, mostly 25/50.
The other final 50 point project was an ad campaign for a robot they had to design and market. The kids had to come up with a feature set and figure out who they would sell it to. They had 3 to 5 minutes to present their idea and tell us why their robot would solve our problems. After the presentation, we discussed what in their design existed today, how some of the technology was 20 years old, how some of it is so hard to do. I ended this with Michio Kaku’s new show How to Build a Robot. Final Project
So what did I learn?
- The CMU lesson software is a good starting point for a lesson, but I needed to add a timed point challenge at the end of each training sesson. I will use the CMU lessons in the future, but not rely on them alone.
- It’s really hard to put this stuff on a midterm exam. Best to not try and give them graded programming challenges every day or two.
- Keeping the kids out of the parts bins is a good idea as long as several classes are sharing the robots. Next year when I have a dedicated class, it won’t be an issue. But not letting them modify the robot beyond the guidelines of the lesson was the way to go.
- Number all the big parts to match the brick and bin.
- I started to have the kids delete their programs from the computer and the robot so others wouldn’t cheat. I don’t have a better way around that right now. I’d like to use USB drives, but we’ve had virus issues, so that’s not allowed. Ideally, LEGO will add password protection.
- Invest in some NXT books. I found a bunch on eBay and half.com and went crazy. If you are only purchasing one of them, buy the book “The Lego Mindstorms NXT Idea Book” by Boogaarts, Daudelin, Davis, Kelly, Levy, Morris, … . This is the book I wish I had before I started the course. It tells you how to do all those things you figure out a little too late, like making your own subroutines (it’s so easy) and how each of the sensors work (if you use more than one ultrasonic sensor at a time, they interfere with each other). Also, books by James Kelly have some good challenges based around a storyline. I think this would be a great way to introduce these robots to a middle school class. I have the Mayan Adventure, his newer one is called The King’s Treasure; I’ll be picking that one up as well.
- I will add the “My Blocks” early on. Next time, after the kids complete the first task of programming the robot to travel in rectangle, I’ll show them how they can make a single “My Block” for a 90 degree right turn and just use it rather than cutting and pasting 5 blocks for each turn. Hopefully, they’ll build their own library of additional blocks as the class progresses.
- Download videos of LEGO projects from YouTube. There are a whole bunch of different walking robots, Rubik’s Cube solvers, and an amazing Sudoku solver that you absolutely must see. I plan to show the walking robots to the summer kids and let them go on their own to design and build their own walking creation. The videos showed the kids the power of the “toys” they were playing with. I will show these and other short robot videos, perhaps one at the start of each class, in an effort to motivate them into doing more.
I was worried I wouldn’t have enough material for the kids to do this for 6 hours a day for a week. I’m pretty sure the projects and videos will make the summer session fly by. It should be fun to let them experiment and build on their own.
HELP: If anyone has good NXT plans or links for a walking robot or a dog, or any other plans I can use for this class, I would really appreciate an email. Use the Contact Me or post a comment. Thanks.
A quick update and then a bit of a review. We purchased 12 Lego NXT robot kits for the classes. I was at first concerned that each class needed their own robots – not a problem. We pre-built the robot that the classes are using. Sharing robots has not been an issue, but we aren’t making major changes to the robots either. Basically, as we move along, another sensor is added and stays added. Students have not been in the parts bins and I like that. The kids work in groups of two and have one computer per robot.
The kits were missing some pieces, Lego is great about sending them out without a hassle. There are two different “Taskbots” described; one in the paper manual you get with the kit, the other in the Carnegie Mellon University (CMU) Robotics curriculum. I found out the hard way, you should make the CMU Taskbot, not the Lego Taskbot if you are using CMU classroom software. It took 30-45 minutes per robot to build them from scratch.
I started off using the CMU projects and worksheets as included in the software. After a week, I had about eight hundred pages to grade and the kids were spending more time answering questions than programming. Some were getting bored. I’m still not unburied.
I dropped the worksheets, they just were getting in the way, and to be honest, they were very repetitive. Instead, I had my students follow the lesson in the lesson video (which is very well done) and when they were finished, I had an additional programming assignment they had to complete. I came up with a shorthand programming language so they could quickly copy the program onto paper. At the basic level, there is an icon based programming language that is very user friendly, but hard to document. Their assignments had to be accurately documented so that I could re-create their program. Many of them can’t seem to get that concept, but they will, it’s on the midterm next week.
Some things that helped:
- Number the robots and kits with a Sharpie. That way you can keep sensors and parts together. Like I said, students haven’t been in the kits, so everything is in good shape 3 weeks into the lessons. Each robot behaves slightly differently, the sensors and motors are not exactly alike, so fine tuning programs works better when you keep coming back to the same robot.
- The software has “profiles” for different classes to use the software. Unfortunately, profiles aren’t password protected. There was some problems with students checking out the work from another class. This is hard to catch and is a real pain. If you can have classroom accounts for each class, you would be in better shape. I didn’t have that luxury this year.
- I pay attention each day to who is out, working hard, and hardly working. Part of their grade is an effort grade, a daily log give me a better sense of history.
What worked and what didn’t:
- The first couple lessons were how to move forward and backward. Again, paperwork went slow, but the lesson was a good one because sensors count up and back. If you move forward 2 rotations and want to move back 2 rotations, the sensors have to move back to zero then back to negative 2. So learning how the rotation sensors worked was important.
- At the end of the lesson, I always suggested the students play with the robot enough to teach me something. They learned to add sounds, speech, pictures to the screen, and a few other tricks early on. I encouraged playing and didn’t hassle them as long as they were busy.
- The turning lessons were tedious. It didn’t help that my students can’t get the concept of diameter of the wheel being related to the distance the wheel turns in a single rotation. It wasn’t a bad lesson, my kids are horrible at math. When they finished the turning work (including too much paperwork), I told them they had to teach the robot to do a Figure-8. It took some of them more than two classes to make that happen. I put an “X” on the floor using electrical tape. It was the starting point and they had to end up somewhere near there when they ended. That was a good addition.
- Next up was the sound sensor. The software walked them through “Clap-on, Clap-Off” where a single clap starts and stops the robot. It went on to teach about programming loops as well. My addition (from the software), one clap on, two claps off. They had to turn in a written program to get credit.
- For each added assignment, I created a demo program so they had an idea what I was looking for. I tended to add lots of flash and silliness to my programs. For instance, for the “Clap-On, Clap-Off” program, it would start with Hello. After one clap, it would say “Green Light” and start moving. After two claps, it would stop and say “Red Light.” It would then pause, spin in place 3 times while screaming, stop and say “Sorry,” then start over again.
- This week was “Follow the Line.” This is a great lesson that appears harder than it is. Using the light sensor, you stay either to the right or left of a thick line made from electrical tape. The robot works but crawls. My addition was for them to get creative and try to make it go faster. I put down two paths using tape, we used one as the race track. Using the original program, a robot takes about 3 minutes to do the loop. The battle has been intense, the first record was set at about 26.7 seconds, today someone did it in 19.5 second. The track is kind of like a go-cart track, mostly oval but with an extra indented curve that makes this quite challenging.
- CMU’s fix to the original slow line tracker is to move the sensor closer to the wheels and go in reverse, but my students blew that away with their creative programming using the original plan. I like my way better.
Next is touch sensing and using infrared sensors to detect objects. Unfortunately, that won’t be for two weeks, we need to start reviewing for midterms, they are next week. Expect part two in about a month.
We’ve discussed a school-wide program to convert student and teacher homes over to the new energy efficient bulbs, perhaps selling the bulbs. We’ve discussed installing a solar hot water heater, but our school doesn’t use much hot water, probably not enough to show a return. I’d like to look into wind energy.
Has anybody tackled this problem? I have done only basic research on the topic. I’ve spoken to our zoning person in the town I live in (I work in Philadelphia), and he says nobody has put one in yet. I’m curious if there are grants or other assistance programs out there to aid schools in bringing this kind of technology to the students.
Parents hate them. Most aren’t any more science literate than their kids. The pressure on the parents to create a decent project is awful. Coming up with a good science experiment project is really hard to do. There are dozens of books on the topic and everybody is clawing at them, trying to find something they can handle.
Kids hate them. They see it as a grade, nothing more. They don’t understand the need for the formality in the presentation. All they know is they don’t win. Now they hate science.
Teachers hate them. Be honest, they are brutal to grade, the work is not worth the effort. Please, no more volcanoes.
OK, now that I got that off my chest, let’s talk about this.
I love doing experiments. I love inspiring kids to think. I make my students experiment constantly. I want them to play in science, find the joy and excitement. I want them to ask questions and be curious. I make them launch rockets and throw balls. If they make a paper airplane in my class, they better make five or ten and tell me what design works best and why. Is science really distilling everything they know about a topic and making it fit on a bent poster board?
I will be doing a science fair in my classroom in about a week. Only I don’t call it that. I call it my “Mythbusters Project.” To be honest, I don’t care if it’s a stupid idea they are testing. I want them to be goofy and have fun. I help them to make sure they are doing good science. I challenge their findings. I make them work together and research. I know, it’s not the county science fair. So what?
You can’t sell someone something they don’t want or need. Really, it’s true. OK, maybe once, but you lost them as a customer forever if you do that. Kids want to be creative, they want to think, they want to learn. They are unbelievably curious. If you don’t think so, leave a pile of mechanical puzzles on the table and don’t draw attention to it. Every one of them will be in the kids’ hands in two minutes. Try it.
Here’s the question you need to ask yourself: What can I do to make this kid love science?